How do I get the server uptime in Node.js?

Question

How do I get a server uptime in Node.js so I can output it by a command like;

if(commandCheck("/uptime")){
  Give server uptime;
}

Now I don't know how to calculate the uptime from the server's startup.

Answer 1

You can use process.uptime() . Just call that to get the number of seconds since node was started.

function format(seconds){
  function pad(s){
    return (s < 10 ? '0' : '') + s;
  }
  var hours = Math.floor(seconds / (60*60));
  var minutes = Math.floor(seconds % (60*60) / 60);
  var seconds = Math.floor(seconds % 60);

  return pad(hours) + ':' + pad(minutes) + ':' + pad(seconds);
}

var uptime = process.uptime();
console.log(format(uptime));

Answer 2

To get process's uptime in seconds

    console.log(process.uptime())

To get OS uptime in seconds

    console.log(require('os').uptime())

Answer 3

What you can do to get normal time format is;

String.prototype.toHHMMSS = function () {
    var sec_num = parseInt(this, 10); // don't forget the second param
    var hours   = Math.floor(sec_num / 3600);
    var minutes = Math.floor((sec_num - (hours * 3600)) / 60);
    var seconds = sec_num - (hours * 3600) - (minutes * 60);

    if (hours   < 10) {hours   = "0"+hours;}
    if (minutes < 10) {minutes = "0"+minutes;}
    if (seconds < 10) {seconds = "0"+seconds;}
    var time    = hours+':'+minutes+':'+seconds;
    return time;
}

if(commandCheck("/uptime")){
    var time = process.uptime();
    var uptime = (time + "").toHHMMSS();
    console.log(uptime);
}

Answer 4

Assuming this is a *nix server, you can use the uptime shell command using child_process :

var child = require('child_process');
child.exec('uptime', function (error, stdout, stderr) {
    console.log(stdout);
});

If you want to format that value differently or pass it through somewhere else, it should be trivial to do so.

EDIT: The definition of uptime seems a little unclear. This solution will tell the user how long the device has been powered on for, which may or may not be what you're after.

Answer 5

I'm not sure if you're talking about an HTTP server, an actual machine (or VPS) or just a Node app in general. Here's an example for an http server in Node though.

Store the time when your server starts by getting Date.now() inside the listen callback. And then you can calculate uptime by subtracting this value from Date.now() at another point in time.

var http = require('http');

var startTime;

var server = http.createServer(function (req, res) {
  res.writeHead(200, {'Content-Type': 'text/plain'});
  res.end('Uptime: ' + (Date.now() - startTime) + 'ms');
});

server.listen(3000, function () {
    startTime = Date.now();
});

Answer 6

To get the unix uptime in ms syncronously:

const fs= require("fs");

function getSysUptime(){

     return parseFloat(fs.readFileSync("/proc/uptime", { 
       "encoding": "utf8" 
     }).split(" ")[0])*1000;

}

console.log(getSysUptime());